Steven Spielberg can’t believe how quickly he was able to make new movie The Post.

The filmmaker has just unveiled the 1970s-set political thriller, which depicts the true story of how journalists from The Washington Post and The New York Times made the decision to publish the Pentagon Papers, documents regarding undisclosed information about the involvement of the U.S. government in the Vietnam War.

Spielberg cast Meryl Streep as publisher Katharine ‘Kay’ Graham and Tom Hanks as editor Ben Bradlee, with the film marking the first time the trio had worked together, and the director was amazed by how “instantaneously” the project progressed.

“A lot of my movies take a long time to develop. I buy books, I develop scripts, years go by, I make other movies instead. It percolates, it comes back into my life, you know I finally get around to making them,” he said at a recent press conference. “And this one, my entire I guess span of 49 years professionally directing, I never had a film come together this quickly.”

While The Post deals with a range of political and social issues, Spielberg was particularly interested in telling Kay’s story, as it was unusual for a woman to be in such a position of power at the time. Having assumed the reins of The Washington Post after her husband’s death, Kay wasn’t taken seriously by her colleagues initially, but eventually became the first female Fortune 500 chief executive.

“The first thing that attracted me to The Post was Katharine Graham, it was her story, was her evolution as a real person of real potential power that did not really have the facility to exercise that power. She hadn’t quite found her centre of gravity, she hadn’t been able to find how to use her own voice,” the 71-year-old shared.

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